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Replication and Reserved Words

You can encounter problems when you attempt to replicate from an older master to a newer slave and

you make use of identifiers on the master that are reserved words in the newer MySQL version running

on the slave. An example of this is using a table column named current_useron a 4.0 master

that is replicating to a 4.1 or higher slave because CURRENT_USER is a reserved word beginning in

MySQL 4.1. Replication can fail in such cases with Error 1064 You have an error in your SQL

syntax.. ., even if a dałabase or łabie named using the reserved word or a łabie having a column

named using the reserved word is excluded from replication. This is due to the fact that each SQL

event must be parsed by the slave prior to execution, so that the slave knows which database object or

objects would be affected; only after the event is parsed can the slave apply any filtering rules defined

by —replicate-do-db[2010], —replicate-do-table [2012], — replicate-ignoredb

[2011], and —replicate-ignore-table [2013],

To work around the problem of database, table, or column names on the master which would be

regarded as reserved words by the slave, do one of the following:

•    Use one or morę ALTER TABLE statements on the master to change the names of any database

objects where these names would be considered reserved words on the slave, and change any SQL

statements that use the old names to use the new names instead.

•    In any SQL statements using these database object names, write the names as quoted identifiers

using backtick characters (').

For listings of reserved words by MySQL version, see Reserved Words, in the MySQL Sen/er Version

Reference. For identifier guoting rules, see Section 9.2, “Schema Object Names".